Cancer, tumors, tumor-related disorders, and neoplastic disease states are serious and often times life-threatening conditions. These diseases and disorders, which are characterized by rapidly-proliferating cell growth, continue to be the subject of research efforts directed toward the identification of therapeutic agents which are effective in the treatment thereof. Such agents prolong the survival of the patient, inhibit the rapidly-proliferating cell growth associated with the neoplasm, or effect a regression of the neoplasm.
Generally, surgery and radiation therapy are the first modalities considered for the treatment of cancer that is considered locally confined, and offer the best prognosis. Chemotherapy treatment of certain cancers typically results in disappointing survival rates but still offer a survival benefit. For example, in patients with non-small cell lung cancer, platinum-based chemotherapy regimens, such as the use of either cisplatin or carboplatin plus one of either paclitaxel, docetaxel, gemcitabine, vinorelbine, irinotecan, etoposide, vinblastine, or bevacizumab is employed. If patients cannot tolerate this therapy, a single agent, such as N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)quinazolin-4-amine, commonly known as erlotinib (Tarceva®), can be used. Erlotinib targets the epidermal growth factor receptor tyrosine kinase which is highly expressed and occasionally mutated in various forms of cancer. If patients fail to respond to an erlotinib treatment, additional conventional treatment offers limited benefit.
Despite erlotinib's approval for the treatment of stage IIIB and IV non-small cell lung cancer, as with most therapeutic agents, side-effects result from its use. For example, common side effects, occurring in greater than 30% of patients taking erlotinib, include, rash, diarrhea, poor appetite, fatigue, shortness of breath, cough, nausea and vomiting. Additionally, less common side effects include infection, mouth sores, itching, dry skin, eye irritation, pulmonary fibrosis, and abdominal pain. Of greater concern, is the growing view that, while utilization of erlotinib for the treatment of tumors may initially shrink the size of the tumor, the tumor may eventually enlarge in size, indicating, among other things, the development of resistance. Erlotinib may be representative of the types of therapeutic agents being used for cancer treatment; in that its use has an effect on cancer, but because of other factors, which are not entirely known, the tumor develops resistance and progresses.
What is needed, therefore, are compositions and/or methods of treatment for cancer which take advantage of the synergy found in a therapeutic combination that could increase the effectiveness of the agents and reduce and/or eliminate the side effects typically associated with conventional treatments.